For the first time since Munich in 1972, there was no organized boycott of the Summer Olympics. Cuba and Ethiopia stayed away in support of North Korea (the IOC turned down the North Koreans' demand to co-host the Games, so they refused to participate), but that was about it.

More countries (159) sent more athletes (9,465) to South Korea than to any previous Olympics. There were also more security personnel (100,000) than ever before given Seoul's proximity (30 miles) to the North and the possibility of student demonstrations for reunification.

Ten days into the Games, Canadian Ben Johnson beat defending champion Carl Lewis in the 100-meter dash with a world record time of 9.79. Two days later, however, Johnson was stripped of his gold medal and sent packing by the IOC when his post-race drug test indicated steroid use.

Lewis, who finished second in the 100, was named the winner. He also repeated in the long jump, but was second in the 200 and did not run the 4x100-relay. Teammate Florence Griffith Joyner claimed four medals–gold in the 100, 200 and 4x100-meter relay, and silver in the 4x400 relay. Her sister-in-law, Jackie Joyner-Kersee, won the long jump and heptathlon.

The most gold medals were won by swimmers–Kristin Otto of East Germany (6) and American Matt Biondi (5). Otherwise, Steffi Graf added an Olympic gold medal to her Grand Slam sweep in tennis, Greg Louganis won both men's diving events for the second straight time, and the U.S. men's basketball team had to settle for third place after losing to the gold medal-winning Soviets, 82-76, in the semifinals.